This proposal is designed to develop an instrument to assess cognition or thinking patterns in normal adults and adult psychiatric patient subjects. The need for such an instrument is documented as part of the rationale. Basically three reasons exist for developing the instrument. Cognitive-behavioral psychotherapies have been developed for treating a wide variety of disorders (eg. depression, obesity, pain, impulse-oriented problems). These treatments are alleged to change cognitions yet no satisfactory measure of these alleged cognitive changes is available. An instrument to measure cognition would assess whether such cognitive changes occur and may predict which patients might respond to such treatments. Secondly, the existing measures of cognition or belief have inherent inadequacies in their design necessitating the development of a new instrument. Thirdly, a measure of cognition would allow testing of the cognitive theory of psychopathology (Beck, 1976). The proposal is designed to further develop the test instrument and scoring system. Specifically, interjudge reliability, test-retest reliability, and concurrent validity studies are proposed. Factor-analyses and item analyses are planned within the limitations of funding. The instrument currently consists of 50 situations to which the subject is asked to give his/her first thought. The answers are scored from rationality-irrationality and for the presence or absence of depressive content. The advantage of this instrument over other tests of belief or cognition is that (a) the socially appropriate or rational answers are not apparent in the instrument itself, and (b) it assesses cognition with respect to a variety of specific areas (eg. family, occupation, friendships, etc.).